This invention relates generally to telescopes, and, more particularly, to a system for adjusting a secondary mirror of a telescope.
In some instances, it is desirable to position a telescope in orbit around the earth to obtain clear images of remote targets such as astronomical phenomena. As used herein, the term “telescope” refers to any device that collects, magnifies, or concentrates light and/or electromagnetic radiation received from and/or transmitted to a distant point. When a telescope is positioned in orbit, the light originating from such remote targets can be collected without the distortion that occurs when that light passes through the earth's atmosphere. Accordingly, several telescopes have been placed in orbit around the earth. In many instances, such space telescopes have been mounted on platforms (satellites).
In one exemplary instance, in a Newtonian type of telescope, the secondary mirror is typically attached to a mount having a plurality of legs and a central housing. The secondary mirror is mounted on a platform upon the central housing that may be adjusted to move the secondary mirror. The adjustment may be manually accomplished if the housing is accessible. Manual adjustment may be very time consuming because of repeated adjustments necessary in a trial and error method. Further, if the system is closed, it must be opened and reclosed. Another problem may be the danger to the optical system from dropped objects, finger prints, etc. If the telescope system is placed in space, normally manual adjustment must occur before launch. The secondary mirror may be placed out of adjustment by vibration, changes in temperature, etc. Even the most ruggedly built system will require minor adjustments in this case.
Active adjustment systems have been in use focusing mechanisms for primary mirrors in photometers mounted onto a spacecraft. In those active adjustment systems, motion (of struts) is constrained to one dimension. This conventional design has constraints that are not necessary in the active adjustment system for secondary mirror.
There is a need for systems that provide an active adjustment of mirrors and specifically of secondary mirrors. There is also a need for systems that provide active adjustment of secondary mirrors in six degrees of freedom. There is also a further need to provide a system with components that can sustain the load during launch without additional constraint devices.